Disposal of human urine and feces has been difficult in remote, heavily trafficked areas. For example, many public restrooms in state and national parks cannot readily be connected to sewage treatment facilities and environmental considerations often effectively prevent use of septic systems. As an alternative to conventional municipal sewage treatment and septic systems, composting vessels have been employed to collect and treat feces and to collect urine from toilets at public restroom facilities where conditions are not otherwise suitable for the installation of waste-treatment facilities.
Collected feces and urine are allowed to remain in the composting vessel under conditions which allow them to decompose by a process known as composting. The compost formed from the feces and urine is then removed from the composting vessel. However, urine contains ammonium ions which can significantly inhibit the composting rate of feces. Often, a relatively high proportion of urine is collected in the composting vessel, thereby substantially reducing or terminating composting of the feces.
One attempt to reduce the concentration of ammonium ions in feces collected in a composting vessel includes draining urine and other liquid waste from feces collected in the composting vessel. Although liquid is separated from the collected feces, ammonium ions can accumulate in the composting feces, thereby decreasing the rate of composting. In addition, flow of a relatively large volume of liquid through collected feces can substantially diminish the rate of composting by reducing the amount of aeration in the collected wastes.
In another attempt, urine and feces are collected separately. However, separation of urine and feces causes the feces to dry, thereby inhibiting composting. Also, urine which is isolated from aeration and bacterial activity generally does not decompose. Water is often evaporated from the urine in isolated storage tanks in order to diminish the amount of storage volume required for urine which is stored separately. However, concentrated urine generates a strong disagreeable odor.
A need exists, therefore, for a new system and method for treating feces and urine which overcome or eliminate the aforementioned problems.